Line Numbers
Add line numbers to text or strip them back off, with start, step, separator and padding options.
How to use it
- Paste your lines into the input panel.
- Pick the mode: Add line numbers or Remove line numbers.
- In add mode set Start, Step, Separator (default ". ") and switch on Pad with zeros when you want aligned columns.
- Click Run. Empty lines are numbered as well.
- In remove mode every line that begins with digits followed by one separator (. ) : | tab or space) loses that prefix; other lines pass through untouched.
Common use cases
- Numbering code snippets before pasting them into a tutorial or a chat reply.
- Restoring a clean list after someone sent you a numbered paste.
- Building aligned numbered output for logs or test output.
- Round-tripping: add numbers here, strip them on the other side.
Why it stays private
The whole transform is a few array operations in your browser tab. Source code, logs and personal notes are never uploaded.
FAQ
Q: Are blank lines numbered too? A: Yes. Numbering follows the physical lines, so an empty line gets its number and an empty body.
Q: What separators does removal recognize? A: One of . ) : | tab or a single space after the digits. A line that does not start with digits is kept exactly as it is.
Q: How does zero padding decide the width? A: It pads to the width of the last number, so 1 to 100 becomes 001 to 100.
Your data stays on this device
Line Numbers runs 100% locally. Everything you paste or drop is processed by your own browser and never transmitted. Nothing is stored on our servers — close the tab and it is gone.
Nothing you type is sent to a server, logged, or used for analytics. The page works even with your network disconnected after first load.